I saw them, they are a very small step in what I believe is the right direction, since you can use a custom textDocument. Anyway what I think would be useful is to jailbreak the QML API. Make the QML C++ API publicly available. Let us derive from the controls, manipulate and customize them with C++, as the Qt team devs themselves do.
I've created my own block editor from scratch using Qt C++ and QML, which is way faster than a regular QML TextArea[1]. Which is funny since it's just a ListView with Blocks (that contain TextAreas).
